2x + x + 10 + x = 110
4x + 10 = 110 (Subtract ten from both sides)
4x = 100 (divide both sides by four)
x = 25
Plug in values to check...
2(25) + 25 + 25 + 10 = 110
50 + 50 + 10 = 110
110 = 110
Mick is 50 years of age.
Sal is 25 years of age.
Eric is 35 years of age.